CI: Specify token when checking out demo

The existing WebAssembly CI works on my repository, but it is failed
here. This is very strange but we still have to solve it.

Combining some dicussion in github-push-action's issue and my own
thought, when checking out demo, the persist-credentials is set to
false, thus the token used for further action should be specified.

See issue: #400

.github/workflows/deploy-wasm.yml

@@ -55,6 +55,7 @@ jobs:
         uses: actions/checkout@v4
         with:
           persist-credentials: false # otherwise, the token used is the GITHUB_TOKEN, instead of your personal access token.
+          token: ${{ secrets.RV32EMU_DEMO_TOKEN }}
           repository: sysprog21/rv32emu-demo
       - name: Create local changes
         if: ${{ steps.changed-files.outputs.any_changed == 'true' ||